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    <title>Document</title>
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<body>
    <h2>数组方法</h2>
</body>
<script>
    let arr=[34,2,23,34,43,23]
  // let res= arr.unshift('全栈')
   let res= arr.shift()
      console.log(res)
      console.log(arr)
   // arr.length
 //  arr.length=2
 //let res=arr.push('hello','2302A')
 // arr[arr.length]='goggoog'


  //arr.length=arr.length-1
   //console.log(arr)
</script>
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